Exadata Dictionary Views

Listed down some Exadata views which can help you to get Exadata related statistics

Get Cell Definition

V$CELL 

GV$CELL 

Exadata cell effectiveness and statistics

V$SYSSTAT 

V$SEGMENT_STATISTICS 

V$SQL 

Historical view of the types and frequencies of the requests being run by a cell.

V$CELL_REQUEST_TOTALS 

Cell Performance Statistics

V$CELL_STATE 

Display Exadata Cell Threads

V$CELL_THREAD_HISTORY

Backup Related View

V$BACKUP_DATAFILE 

Exadata Storage Index Part-1

• It is not like traditional index which is in database. This is the feature of storage software and useful to eliminate IOs.
• Storage Index filter out data from the consideration. 

• It works by storing minimum and maximum column values for disk storage units, which are 1 Megabyte (MB) by default.
• Because SQL predicates are passed to the storage servers when Smart Scans are performed, the storage software can check the predicates against the Storage Index metadata (maximum and minimum values) before doing the requested I/O.

• Any storage region that cannot possibly have a matching row is skipped.

• There are no tuning technique or documents for storage index as it maintain by storage software only.

Storage Indexes consist of a minimum and a maximum value for up to eight columns. This structure is maintained for 1MB chunks of storage (storage regions). Storage Indexes are stored in memory only and are never written to disk.

Storage index is not static, whenever we shutdown or reboot storage server it will be removed and once server comes up storage server automatically create index.

Now we will see that how storage index actually work while executing the query on the DB server.

Click on image to enlarge.

Now we are executing below query on this table.

SQL> select * from TABLE where c>7;

In this case first query will go to the storage index and it will check min and max number for rows of first set but 7 is not fitting in Min and Max for rows of first set so, it will eliminate to check the data of that rows and it will move to second set of rows. 

Exadata Storage Server Shutdown/Startup procedure

Shutdown Procedure

1. Execute below command to check if there is any offline disk    

cellcli > list griddisk attributes name where asmdeactivationoutcome != ‘ yes’

if it write anything then it's not safe to offline the storage server as disk redundancy will not maintained properly.

2. Inactivate all the griddisk with below command if step one positively executed with no output

Cellcli > alter griddisk all inactive

3. Verify whether all disks are inactive or not with below command

Cellcli > list griddisk where status =! ‘inactive’

If all disk grid disks are inactive then we can proceed to shutdown the storage server.

Startup Procedure

1. Start the cell. All cell services will come up automatically.

2. Bring all disk online

Cellcli > alter griddisk all active

3. Verify whether disks successfully came online or not

Cellcli > list griddisk attributes name, asmmodestatus

All disks should come online. If any of the disk is not online then wait sometimes to change the disk status.


You can follow our Exadata Certification Question Bank to achieve maximum success in your Exadata certification exam.

Cellcli - Alter

CellCLI> alter cell shutdown services rs --> To shutdown the Restart Server service 
CellCLI> alter cell shutdown services MS --> To shutdown the Management Server service 
CellCLI> alter cell shutdown services CELLSRV --> To shutdown the Cell Services 
CellCLI> alter cell shutdown services all -->To shutdown the RS, CELLSRV and MS services 
CellCLI> alter cell restart services rs 
CellCLI> alter cell restart services all 
CellCLI> alter cell led on
CellCLI> alter cell led off 
CellCLI> alter cell validate mail
CellCLI> alter cell validate configuration 
CellCLI> alter cell smtpfromaddr='cell07@orac.com' 
CellCLI> alter cell smtpfrom='Exadata Cell 07' 
CellCLI> alter cell smtptoaddr='satya@orac.com' 
CellCLI> alter cell emailFormat='text' 
CellCLI> alter cell emailFormat='html' 
CellCLI> alter cell validate snmp type=ASR - Automatic Service Requests (ASRs) 
CellCLI> alter cell snmpsubscriber=((host='snmp01.orac.com,type=ASR')) 
CellCLI> alter cell restart bmc - BMC, Baseboard Management Controller, controls the compoments of the cell. 
CellCLI> alter cell configure bmc 
CellCLI> alter physicaldisk 34:2,34:3 serviceled on
CellCLI> alter physicaldisk 34:6,34:9 serviceled off 
CellCLI> alter physicaldisk harddisk serviceled on 
CellCLI> alter physicaldisk all serviceled on 
CellCLI> alter lun 0_10 reenable 
CellCLI> alter lun 0_04 reenable force 
CellCLI> alter celldisk FD_01_cell07 comment='Flash Disk' 
CellCLI> alter celldisk all harddisk comment='Hard Disk' 
CellCLI> alter celldisk all flashdisk comment='Flash Disk' 
CellCLI> alter griddisk RECO_CD_10_cell06 comment='Used for Reco'
CellCLI> alter griddisk all inactive 
CellCLI> alter griddisk RECO_CD_11_cell12 inactive 
CellCLI> alter griddisk RECO_CD_08_cell01 inactive force 
CellCLI> alter griddisk RECO_CD_11_cell01 inactive nowait 
CellCLI> alter griddisk DATA_CD_00_CELL01,DATA_CD_02_CELL01,...DATA_CD_11_CELL01 inactive 
CellCLI> alter griddisk all active 
CellCLI> alter griddisk RECO_CD_11_cell01 active 
CellCLI> alter griddisk all harddisk comment='Hard Disk' 
CellCLI> alter ibport ibp2 reset counters
CellCLI> alter iormplan active 
CellCLI> alter quarantine 
CellCLI> alter threshold DB_IO_RQ_SM_SEC.PRODB comparison=">", critical=100 
CellCLI> alter alerthistory

Exadata Components

Hardware Components

-Database Node (Database Server)
-Cell Storage (Storage Server)
-Infiniband switch
-Cisco network switch
-KVM
-PDU
-Rack
-Flash Cache


Software Components

-Storage Software
-Operating System (Linux/Solaris)
-Oracle Database Software